Air-check device



F. E. CHEESMAN.

AIR CHECK DEVICE.

APPLICATION FILED OCT. 23, 1919.

1,428, 1&5. P nt dsept- 5,1922.

lNVENTOR Fredgrz'c E. Cfieesman ATORNEY Patented Sept. 5, 1922!.

FREDERIC E. C'HEESMAN, 0F BROOKLYN, NEW YORK.

AIR-CHECK DEVICE.

Application filed October 23, 1919. Serial No. 332,591.

To all whom it may concern.

Be it known that I, F nnnnnrc E. CHEns- MAN, a citizen of the United States, residing at Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Air-Check Devices, of which the following is a specification, reference being had therein to the accompanying drawing.

My invention relates to improvements in air check devices for exposing apparatus for cameras and is in the nature of an improvement upon my U. S. Letters Patent 766,874, wherein the air release for timing the exposure involves the adjustment of concentric tubes, whereas in my present construction I provide a knurled screw which may and quickly'adjusted by be conveniently hand and give a very accurate adjustment of air release thereby providing a very desirable adjustment for the exposure.

Referring to said drawings Fig. 1 is a plan View partly broken away and partly in cross-section illustrating an embodiment of my invention. Fig. 2 is a view of the upper part of the same looking from left to right at Fig. 1.

8 indicates the piston chamber into which air is compressed from the bulb at in the usual manner beyond the Valve 5, the outlet or escape being indicated by the reference character 6. The air after entering the passage 7 escapes by one or more of the holes 8 which are in the path of the knurled screw 9 so that when the screw is down in the po-' sition shown in Fig. 1 a very long exposure is provided for, the aironly being able to escape by the lower and more restricted hole, whereas if the screw 9 were lifted say a half inch, the air would escape through all of 40 the holes 8 and the siderably shortened.

Of course it will be understood that various modifications may be made in the conexposure would be construction and arrangement of parts without from. the spirit of the invention comprising an in the direction 

